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180ways2slide
06-03-2008, 07:50 PM
i been running my sr for about 2 months now and i noticed my catch can at 22 psi is fulling fast so i decided to do a compression test and my numbers came up 120,120,119,120 and car is still pulling really strong. test was done fully warm but I DID NOT OPEN THROTTLE. how much of a difference will the wot make??
mods
sr20det w/ 2500 miles after rebuild
cp pistons 8.5:1 020 over
eagle rods
built head no port
264 cams etc. etc
also what are compression #s for built motors w/ lower compression??
97KATURBOSILVIA
06-03-2008, 08:22 PM
do the comp test at wot, then post numbers, also just because catch can is filling, doesnt always mean bad internals. 22 psi thats work on a turbo and it could be going and not your block. the last sr i tested was 8.8 comp ratio and pushed 150's. gl
koukimonster139
06-03-2008, 08:25 PM
turbine info?




maybe its shot
180ways2slide
06-04-2008, 04:00 AM
the turbo is in good shape has no shaft play its a 60-1 w/ . 63 ar any more
info on low compression motors and how much diff does wot make on comp test
Sileighty_85
06-04-2008, 07:09 AM
8.5 is stock compression ,so its not lower
a rebuilt SR with .20 over bore and 1.5 mil H/G is compression is gonna be 150ish.
difference with WOT usually 5-10psi so 120 even 130 is pretty low
calico
06-04-2008, 09:07 AM
i'm not sure about the whole 5-10 psi at WOT... i just did a compression test on my accord and i checked the gauge and it said 150-155 psi. then i remembered i didn't open up the throttle and i did it again. all the cylinders jumped up around 175. obviously these are 2 completely different motors but that's my experience between WOT and not during a compression test. i suggest you redo it at WOT, it takes all but 5 minutes
Sileighty_85
06-04-2008, 09:19 AM
big differnce between high comp and low com engines

I did an SR a while ago with closed throttle it read 140 or 145
did again with WOT and then went to 150
calico
06-04-2008, 09:28 AM
FWIW, my accord is only 8.8:1 and a stock SR is 8.5:1 but yea, i know what you mean
Sileighty_85
06-04-2008, 09:30 AM
FWIW, my accord is only 8.8:1 and a stock SR is 8.5:1 but yea, i know what you mean

seriously its only 8.8:1 thats low for an N/A